The invention relates to a lifting/pull-sucker drive mechanism for a sheet-processing machine, more particularly, for a separating or singling element thereof.
The published German Patent Document DE 195 22 901 C1 discloses, for example, a lifting-sucker drive mechanism wherein a suction-intake height of the lifting sucker is adjustable so that there is no change in the height at which the sheet is transferred from the lifting sucker to a downline pull or forwarding sucker. No drive or transmission for the pull-sucker movement is disclosed. Such a pull-sucker drive mechanism, however, has become known heretofore, for example, from the published German Patent Document DE 196 01 470 A1. This drive mechanism has a number of pull suckers, which execute a reciprocating translatory transporting movement through the intermediary of a cam-controlled transmission and a guide.
It is accordingly an object of the invention to provide a combined lifting/pull-sucker drive mechanism which has a compact construction.
With the foregoing and other objects in view, there is provided, in accordance with the invention, a lifting/pull-sucker drive mechanism for a separating element of a sheet-processing machine, having a drivable control cam for moving at least one lifting sucker, and having a drivable control cam for moving at least one pull sucker, respectively, comprising a pivotable control cam for synchronizing a lifting movement of the at least one lifting sucker and a pulling movement of the at least one pull sucker.
In accordance with another feature of the invention, the pivotable control cam is capable of effecting an adjustment of a transfer position at which a sheet is transferred from the lifting sucker to the pull sucker, and a transporting height of the sheet.
In accordance with a further feature of the invention, the lifting sucker is mounted so as to be controllable by the drivable control cam for moving the lifting sucker, and the pull sucker is mounted so as to be controllable by the drivable control cam for moving the pull sucker.
In accordance with an added feature of the invention, the control cams are mounted on a common shaft.
In accordance with an additional feature of the invention, the lifting sucker and the pull sucker, in a lifted position of the sheet, are disposed at an angle to a sheet pile.
In accordance with yet another feature of the invention, the lifting/pull-sucker drive mechanism include a compression spring for ensuring engagement of a control roller with the control cam for moving the lifting sucker, and of a control roller with the pivotable control cam, and including a compression spring for ensuring engagement of a control roller with the drivable control cam for moving the pull sucker, and of a control roller with the pivotable control cam.
In accordance with a concomitant feature of the invention, the pivotable control cam is formed as a segment cam.
A particular advantage afforded by the invention is that the lifting-sucker drive mechanism for the lifting sucker or suckers and the pull-sucker drive mechanism for the pull sucker or suckers have a common guide. In this way, the transfer of sheets from the lifting sucker to the pull sucker takes place at a common vertical level.
The common guide is advantageously formed as a pivotable segment cam. Due to this feature, it is possible to provide an adjustment or setting of a suction-intake height of the sheet, a height at which the sheet is transferred from the lifting sucker to the pull sucker, and a transporting height of the sheet by a single, stationary actuating or setting device.
In an advantageous configuration, sheet transfer from the lifting sucker to the pull sucker and the succeeding transportation of the sheet by the pull suckers take place with the trailing sheet edge at a slight upwardly directed angle xcex1. This feature makes it possible for the carrying air produced by blowing or blast devices to pass with very good effect beneath the sheet which is to be transported. The arrangement of the various control cams for the lifting movement and transporting movement, and the additional sensor or feeler cam all on a common drive shaft optimizes the compact construction of the drive mechanism according to the invention.
Provision is advantageously made for the lifting sucker to execute a translatory movement in addition to a lifting movement. This feature increases the time slot or window for the sheet transfer from the lifting sucker to the pull sucker, with the result that the quality of transfer is improved.
Thus, in general, provision is made, in a lifting/pull-sucker drive mechanism of a separating element, i.e., a suction head, of a sheet-processing machine, for the lifting suckers and pull suckers to be controlled independently of one another, and for the height adjustment of the lifting and pull sucker to be effected by a common control cam.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a lifting/pull-sucker drive mechanism for a sheet-processing machine, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, wherein: